• 전기학회논문지P
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• 제51권3호
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• pp.155-160
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• 2002

This paper focuses on the problem of local obstacle avoidance of mobile robots. To solve this problem, the safety direction section search algorithm is suggested. This concept is mainly composed with non-collision section and collision section from the detecting area of laser scanning sensor. Then, we will search for the most suitable direction in these sections. The proposed local motion planning method is simple and requires less computation than others. An environment model is developed using the vector space concept to determine robot motion direction taking the target direction, obstacle configuration, and robot trajectory into account. Since the motion command is obtained considering motion dynamics, it results in smooth and fast as well as safe movement. Using the mobile base, the proposed obstacle avoidance method is tested, especially in the environment with pillar, wall and some doors. Also, the proposed autonomous motion planning and control algorithm are tested extensively. The experimental results show the proposed method yields safe and stable robot motion through the motion speed is not so fast.

• 동력기계공학회지
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• 제20권6호
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• pp.80-86
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• 2016

In this study, The watertight damper was designed to improve conventional DN 350A butterfly valve. The FSI(Fluid-Structure Interaction) analysis has performed to investigate the safety factor for the watertight damper. When watertight damper of disk was closed, the disk of pressure value is constant. However depending on the opening angle of disk, the flow velocity and pressure are changed. The maximum velocity was appeared at the end of disk on the small outlet area of duct. When the opening angel of disk is $90^{\circ}$, the maximum velocity was appeared at the center of ending disk. So we were found the opening angle of disk is bigger, the flow rate is increased and velocity is also increased from the result of FSI analysis. We can find the least deformation and stress when the opening angel of damper is $90^{\circ}$. When the $45^{\circ}$ opening angle of disk, the largest deformation and stress was found and the minimum safety factor 1.3 was calculated. As a result, we found that the structure of watertight damper is safe enough irrespective of opening angel.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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• 제24권3호
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• pp.17-27
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• 2018

Purpose: This study aims to examine spatial characteristics of emergency department Chronologically through case studies; and to consider the social implication of these spatial changes. Methods: In this study, a total of eight emergency departments, one for each period, were selected in order to analyze the spatial characteristics. The spatial maps of Space Syntax were employed for analyzing case studies. Results: The spatial configuration of emergency department has been changed from five or more emergency department specialties to four or less specialties such as psychiatric, pediatrics, emergency, and trauma. In the case of care initiation area, the concentrated arrangement mode was switched from the distributed arrangement mode. The spatial maps indicate that it can be seen that the tree structure changes to an annular structure emphasizing the connection between the spaces in the emergency department. This shows that the space efficiency, safe, visual control and flexibility in the planning of the emergency department are important factors affecting the spatial structure of the emergency department. Implications: In the future, it is expected that Korean emergency department will be more focused on efficiency, safe, visual control, and flexibility in the planning as in the case studies of the United States.

• 한국안전학회지
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• 제20권1호
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• pp.143-147
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• 2005

Immediate responsibilities for occupational health and safety (OHS) management reside in business proprietors and supervisors whose voluntary participation in OHS educational programs, not legal sanctions, may thus lead to safe and pleasant work environments. This study investigates how to promote the effectiveness of OHS educational programs to draw voluntary participations in such programs in Korea To this end, drawbacks of current practices in OHS education are first analyzed, and then OHS related policies in advanced countries in the area of disaster prevention such as United States and Germany, are also scrutinized. Based on the preliminary investigations, the following propositions are made to lay out the foundation for promoting effective OHS educational programs in Korea: improvement of government regulations, revitalizing job training initiatives, on-site OHS education, compensation and incentive programs for OHS education. These propositions may also facilitate the deployment of disaster prevention activities across the organization and prevent various occupational disorders (for example, musculoskeletal disorders). This study emphasizes that monolithic OHS education systems led by regulatory agencies may not be efficient to ensure healthy and safe work environments. Globally competitive OHS educational systems may be established only when they are based on the health and safety requirements specified by proprietors and workers.

• Archives of Plastic Surgery
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• 제45권3호
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• pp.214-221
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• 2018

Clarification is needed regarding the definitions and classification of groove and hollowness of the infraorbital region depending on the cause, anatomical characteristics, and appearance. Grooves in the infraorbital region can be classified as nasojugal grooves (or folds), tear trough deformities, and palpebromalar grooves; these can be differentiated based on anatomical characteristics. They are caused by the herniation of intraorbital fat, atrophy of the skin and subcutaneous fat, contraction of the orbital part of the orbicularis oculi muscle or squinting, and malar bone resorption. Safe and successful treatment requires an optimal choice of filler and treatment method. The choice between a cannula and needle depends on various factors; a needle is better for injections into a subdermal area in a relatively safe plane, while a cannula is recommended for avoiding vascular compromise when injecting filler into a deep fat layer and releasing fibrotic ligamentous structures. The injection of a soft-tissue filler into the subcutaneous fat tissue is recommended for treating mild indentations around the orbital rim and nasojugal region. Reducing the tethering effect of ligamentous structures by undermining using a cannula prior to the filler injection is recommended for treating relatively deep and fine indentations. The treatment of mild prolapse of the intraorbital septal fat or broad flattening of the infraorbital region can be improved by restoring the volume deficiency using a relatively firm filler.

• 한국항해항만학회지
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• 제46권5호
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• pp.435-440
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• 2022

The development and introduction of a Maritime Autonomous Surface Ship (MASS) are some of the most important changes leading to the fourth industrial era in the maritime area. The term 'MASS' refers to a ship operating independently, without human intervention, to reduce maritime accidents caused by human errors. Recent UK findings MASS also noted that particularly the dynamic positioning system will be considered to apply as newly function to a MASS. The DP system, a ship system developed decades ago and used for specific purposes like offshore operations, provides various functions to facilitate the accurate movements of the vessel, and operators can make decisions within the DP system, in addition to the ordinary ship system. In this paper, it would like to present the connection and application method with the main technical elements of the DP system in connection with the main technology of the DP system to achieve the safe operation of a MASS. In particular, among various position reference systems, the capability plot function of DP system, and the "follow target" mode in the operation mode are attractive functions that can contribute to the safe operation of autonomous ships.

• Journal of Korean Neurosurgical Society
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• 제66권2호
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• pp.172-182
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• 2023

Objective : The blood-brain barrier (BBB) is an obstacle for molecules to pass through from blood to the brain. Focused ultrasound is a new method which temporarily opens the BBB, which makes pharmaceutical delivery or removal of neurodegenerative proteins possible. This study was demonstrated to review our BBB opening procedure with magnetic resonance guided images and find specific patterns in the BBB opening. Methods : In this study, we reviewed the procedures and results of two clinical studies on BBB opening using focused ultrasound regarding its safety and clinical efficacy. Magnetic resonance images were also reviewed to discover any specific findings. Results : Two clinical trials showed clinical benefits. All clinical trials demonstrated safe BBB opening, with no specific side effects. Magnetic resonance imaging showed temporary T1 contrast enhancement in the sonication area, verifying the BBB opening. Several low-signal intensity spots were observed in the T2 susceptibility-weighted angiography images, which were also reversible and temporary. Although these spots can be considered as microbleeding, evidence suggests these are not ordinary microbleeding but an indicator for adequate BBB opening. Conclusion : Magnetic resonance images proved safe and efficient BBB opening in humans, using focused ultrasound.

• KIEAE Journal
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• 제12권5호
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• pp.53-61
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• 2012

As aging society progresses, it is necessary to establish a housing standard that provides a healthy, safe, and convenient environment for the elderly. The objective of the study is to propose a housing space standard that is geared towards elderly living in the urban area. Three steps were taken to attain the objective. First, characteristics of housing preference, spatial usage and furniture preference of the elderly were attained through a survey. The survey was conducted targeting the respondents of the ages 60 to 79 living in three different administrative districts in Seoul. Second, the required floor space to perform individual specific behavior using anthropometric dimension of the elderly was investigated by literature review. Lastly, floor space of each space is suggested combining each area for individual specific behavior which reflects characteristics of housing preference and spatial usage. The results of the research as follows. A bedroom was planned, which includes the function of receiving guests by giving the area for the placement of a sofa. The space for the use of dinning table for two person was planned in the kitchen and The space for the behavior of showering on a chair was planned in a bathroom. Lastly, the space for the behavior of taking off shoes on a chair was considered in the entrance area. Consequently, $35.4m^2$ is suggested as the necessary floor space for the elderly housing considering the characteristics of the elderly in urban area. However, because of space composition and space for accessibility, the additional space should be considered to plan the elderly housing.

• 한국정보통신학회논문지
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• 제23권5호
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• pp.613-621
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• 2019

시중에 가장 많이 보급 된 도어락의 경우 1차원적 문제로 가장 많이 사용하는 영역이 닳아 특별한 공격방법을 사용하는 것이 아닌 닳은 영역으로 하여금 비밀번호 유추를 가능하게 한다. 이를 해결하고자 번호를 섞어 무작위로 표출하는 키패드 등 다양한 방법들이 소개되고 있지만 이 역시 완벽하게 안전하지 못 하다. 여태까지 나온 모든 해결법의 공통점은 키패드를 누르는 영역이 고정되어 있다는 점이다. 본 논문에서는 그 점을 역으로 생각하여 키패드 전체 영역 안에 전체 영역보다 작은 새로운 영역을 만들어 새로운 영역의 키패드를 무작위하게 움직이게 하여 비밀번호를 유추하지 못 하게 한다. 본 기법을 사용할 경우 키패드의 번호는 그대로 둠에도 불구하고 shoulder surfing attack 등이 불가능하여 새로운 유형의 키패드를 최초로 제안한다.

• 대한안전경영과학회지
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• 제15권3호
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• pp.93-103
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• 2013

In recently, a growing concern for the health of urban residents increased interests in a variety of outdoor activities simply be done in terms of cost and time. They are specially interested in low-impact and safe exercises around residential or working area. Walking is the one of easily doing exercise in daytime or nighttime near residential area. The sidewalks of boulevard near the residential area is the best place for exercise because of easy access and the green space with roadside trees. However, if the nighttime is not guaranteed the proper lighting condition, the possibility of exposure to crime and the threat to pedestrian safety can be increased. Because roadside trees are one of the potential obstacle for lighting condition, supplementary lightings are important to mitigate interruption for safety. To meet such a need, the purpose of this study is to propose a simulation approach which improves lighting condition on sidewalks of boulevard with variety of roadside trees. To do so, the simulation approach is applied for analyzing the interrupted condition by classified five standard types of roadside trees considering the growth of them and finding optimal layout of supplementary luminaires by lighting types. The results of this approach shows that it is useful for assessing the safety of pedestrian in nighttime.